Alarm-clock.



Patented July 3], I900.

L. scm r. ALARM CLOCK.

(Application filed Dec. 8, 1899.)

(No Model.)

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NETED Saree FFEQEQ ALARM-CLOCK.

SPECIFICATION forming part of Letters Patent No. 654,677, dated July 81, 1900. Application filed December 8 1899. Serial No. 739,686. (No model.)

To all whom it may concern:

Be it known that I, LUDWIG SOI-IIFF, a subject of the German Emperor, residing at Wilmersdorf, near Berlin, Germany, have invented certain new and useful Improvements in Alarm-Clocks, of which the following is a full, clear, and exact description.

In alarm-clocks of ordinary construction the release of the spring mechanism operating the alarm is effected by an eccentric fast on one of the time-indicating spindles and its handthus, for instance, the hour or minute hand the moment the hand in quest-ion or the eccentric Which is driven by the clockwork has attained a certain position. The position occupied by the various parts of the mechanism in order toei'fect the alarm is either permanent-cl c., it may correspond with the po sition to which the hand is adj ustedor it is of itself adjustable, in which case it is gen erallyindicated by means of a separate alarmhand. Theeccentricmaybevariouslyshaped. It may consist of a disk having a peripheral notch or a cylinder having a facial depression or a disk provided with a pin or the like. The release of the alarm device is generally effected directly by the movement of the detent-lever into the notch or depression, orit may take place owing to a movement of the release disk or eccentric at the expiration of the predetermined period. The notch,which either directly or indirectly allows of the movement of the detent-lever, has a sharp fall at one side and a gradual incline at the other in order to effect the release of the detent-lever suddenly, while the further movement of the release-eccentric will arrest the alarm device by moving back the dctent-lever. It is, however, in many cases advisable to avoid arresting the alarm mechanism by the continued rotation of the shaft to which the release-eccentric is keyed. This is effected according to the present invention by connecting the release-eccentric to the shaft driven by the clockwork by means of a coupling, which is automatically uncoupled as soon as the alarm mechanism has been released, thus enabling the release-eccentric to remain in its freed or release position during the further rotation of the spindle driven by the clockwork, while the arrest of the alarm mechanism can only be effected by the fun:

ther movement of the release-eccentric by hand. v i

In order to render the present specification easily intelligible, reference is had to the accompanying drawings, in which similar letters of reference denote similar parts throughout the several views. j

Figure l is a front elevation of the parts of an alarm device necessary for properly illustrating the object of the present invention, and Fig. 2 a sectional side elevation of Fig. 1. Fig. 3 is a front elevation of a modified form of the device, and Fig. 4 a sectional side or end elevation of Fig. 3.

For the purposes of the present specification it has been assumed that the release of the alarm-lever is effected by a cam-notch in the release-disk-c'. e. ,by means of a cam-disk.

a is the detent-lever for the alarm mechanism, which is held against the releasing disk or cam c by means of a spring I). The alarm mechanism is not illustrated, not forming part of the present invention. The de tent-lever will release the alarm mechanism as soon as the notch of the cam comes into contact With its free end. This position of the cam will be attained as soon as the hand (Z reaches the point indicated by 0 on the dial e. The cam or eccentric c is loosely mounted on the spindle f, and the said spindle f is mounted in the axial boring of the wheel 9, so as to move with the said wheel g when the latter is driven by the clockwork. The parts hitherto described are exactly the same in both modifications.

In the device shown in Figs. 1 and 2 a ratchet gear h is mounted at the rear of the eccentric or cam c on the spindle J, said gear being, however, fast on the said spindle. On the rearfaco of the cam c a pawl t is mounted, which is retained against the teeth of the ratchet-wheel h by means of a spring 7o, thus coupling the cam c with the Wheel h-i. 6., the spindle f. Shortly after the parts have attained the release position the ratchet 2' will strike a pin m and be turned on its pivot, thus releasing the wheel h. Thus the cam will remain stationary and the alarm will con tinue to operate. If, however, the hand or the eccentric is turned by hand in the direction of the arrow, Fig. 1, the pawl 1' will be forced past the pin on and will then be free to engage the ratchct wheel it again, thus coupling the cam and spindle. The detentlever a will also be moved into operative position by the cam-surface of the notch or the cam. iVhen the cam c is moved by hand as soon as it and the spindlefhave been coupled, the latter will have to overcome the friction in the boring of the wheel g, the parts being so adjusted that this friction shall be sufiicient to move the spindle with the wheel 9 when the latter is driven by the clockwork, as hereinbefore set forth.

According to the device illustrated in Figs. 3 and 4, the rear face of the cam c carries a brake-band 0, which is tightened onto the brake-disk 1), fast on the spindle f, by turning the lever 12, which is pivotally mounted on the said cam-face. The lever n is a sort of tumbler, one finger of which is operated by the spring q to operate or tighten the brakeband 0, and thus to couple the cam c to the spindle f. Shortly after the alarm has been set in operation the other finger of the tumbler n strikes the pin '1, which is stationary, and thus releases or loosens the brake-band 0, throwing the brake out of operation and uncoupling the cam c from the spindle f. Thus the cam will remain stationary and the alarm device will remain freed, however many revolutions the spindle f may be rotated. If, however, the hand or the cam cis turned by hand in the direction of the arrow, Fig. 3, the tumbler n will pass the pin 7' and the spring (1 will again cause the brake-band 0 to couple the cam and brake-disk p.

I claim as my invention- 1. In an alarm-clock having a detent-lever to arrest the alarm mechanism, and an operating-cam for the detent-lever, driven by the clockwork, the combination of means for coupling the release-cam to the spindle driven by the clockwork, and for automatically rendering the said coupling ineffective as soon as the alarm has been operated, the said cam being subsequently adjusted by hand in the manner and for the purpose substantially as described.

2. In an alarm-clock, the combination ofa detent-lever for the alarm mechanism, a detent-lever-operating cam loosely mounted on the hand-spindle of the clockwork, means for coupling the said cam to the spindle and for automatically releasing the said coupling as soon as the alarm has been set going, the said cam being connected to the hand of the clockwork-spindle by means of a frictioncoupling, which will yield when the said cam is turned by hand in the manner and for the purpose substantially as described.

In witness whereofI have hereunto set my hand in presence of two witnesses.

LUDIVIG SCIII FF.

Witnesses:

HENRY I'IASPER, WOLDEMAR HAUPT. 

